Table 1.

List of common materials for flexible microfluidics.

Materials	Tg 1 (°C)	Young’s Modulus	Advantages	Disadvantages	Fabrication Techniques	References
PDMS	−125	<1000 kPa	low Tg, low shear and Youngs modulus, high optical transparency, durability, gas permeability	hydrophobic nature, incompatibility with solvents	soft lithography, plasma-enhanced bonding	[63,69,70,73,74]
Ecoflex	NA	40 kPa	low Young’s modulus, highly flexible, high tear strength, and large elongation	non-transparent, high viscosity, incompatible with plasma bonding	soft lithography	[27,77,78,114,115]
Parylene	<90	2.7–4 GPa	biocompatibility, low water absorption, transparent, solvent resistance, surface conformality	costly, complicated fabrication, hard to handle, low adhesion to substrates	vapor deposition bonding	[84,85,86,87,88,89,90,116,117]
PI	300–400	2.5 GPa	biocompatibility, high thermal stability, good sealing properties, chemical inertness	opaque, moisture absorption	lamination, sacrificial layer techniques, wet/dry etching, hot embossing	[93,94,95,96,97,98,103,104,116]
OSTE	25–70	0.25–2 GPa	scalable commercial production possibility, low polymerization shrinkage stress, direct lamination and bonding	very high OS ratios can lead to residual monomers that may affect cells and proteins	soft lithography	[105,106,108,118]
PET	69–78	2–2.7 GPa	good gas and moisture barrier properties, chemically inert, recyclable	poor chemical resistance, needs surface treatment for bonding due to the low plasma bonding strength	moulding by hot embossing, thermal bonding	[27,91,92,119]

¹ Glass transition temperature.